E30 series BMW 3

since 1983-1994 of release

Repair and car operation

+ 1. Maintenance instruction
+ 2. Maintenance
+ 3. Engine
+ 4. Cooling system
+ 5. Heating and ventilation
+ 6. Fuel system
+ 7. Exhaust system
+ 8. Transmissions
+ 9. Coupling
- 10. Brake system
   10.2. Specifications
   10.3. Anti-blocking system (ABS)
   10.4. Blocks of disk brakes
   10.5. Support of a disk brake
   10.6. Brake disk
   10.7. Blocks of drum-type brakes
   10.8. Main cylinder of brakes
   10.9. Vacuum amplifier of brakes
   10.10. Cable (ы) hand brake
   10.11. Adjustment of the hand brake
   10.12. Mechanism of the hand brake
   10.13. Brake pedal
   10.14. Switch of a signal of braking
   10.15. Hoses and lines of a hydraulic actuator of brakes
   10.16. Air removal from a hydraulic actuator of brakes
+ 11. Running gear
+ 12. Body
+ 13. Electric equipment
+ 14. Good advice

10.9. Vacuum amplifier of brakes


Returnable spring of a pedal of a brake (and), lock ring of an axis of a pedal (b) and axis (c)

On an insert the removed axis of a pedal and a bracket of fastening of an axis is shown.

Drive of the vacuum amplifier

1. Dustproof cover

2. Holder

3. Screen

4. Air filter


1. On the idle engine press a brake pedal until then while the course of a pedal will not cease to change.
2. Press and hold a pedal, then start the engine. If the pedal slightly goes down, the cylinder is serviceable.

Tightness check

1. Start the engine and later 1–2 mines stop. Slowly press a pedal several times. If the first course of a pedal gradually decreases after the second or third time, the vacuum amplifier is tight.
2. Press a brake pedal on the working engine and, holding a pedal, stop the engine. If during 30 seconds the pedal does not move, the vacuum amplifier is tight.

The faulty amplifier of brakes is subject to replacement.

Removal and installation

1. Remove the main brake cylinder.
2. Disconnect from the amplifier a vacuum hose.
3. From salon remove a box for trifles and the bottom left facing panels on the left side.
4. Remove a bracket of fastening of an axis and remove a fork axis, disconnect a pusher from the lever (on cars with the right wheel) or from a pedal (on other cars). On cars with the left wheel also disconnect a returnable spring of a pedal of a brake.
5. Unscrew four nuts of fastening (shooters) and get the vacuum amplifier from a motor compartment.
6. Check a condition of the porous filter. If it is polluted, wash out it in weak soap solution. It is not possible if to wash out, replace the filter.
7. Installation is carried out upside-down. Tighten nuts of fastening of the amplifier with the set moment. Before dressing a cover on the filter be convinced that dredging in the filter is displaced concerning dredging on a damper on 180 °.
8. Adjust distance And (distance from the center of an axis of a fork on a brake pedal to a partition / wall of a motor compartment). Tighten a lock-nut, then adjust height and a free wheeling of a pedal of a brake, and also the switch of a signal of braking. Nuts of fastening of the amplifier tighten with the moment of 22-24 N of m.


On and/m with the right wheel the pedal of a brake is on the right side of salon, it is connected to the left side in bulk. Adjustment of draft is carried out on the left side, however the distance is measured on the pedal.

9. Establish the main cylinder and attach a vacuum hose.
10. Check work of brakes.